1. Field of the Invention
This invention, in general, relates to cosmetic compositions. More specifically, this invention relates to natural sunscreen compositions and processes for producing the same.
2. Description of the Related Art
Human skin is sensitive to solar rays and overexposure to sun can cause not only simple sunburn or an erythema, but also burns of varying severity. The other negative effects of over-exposure to solar rays are, tanning, immune suppression, photosensitivity or drug related photosensitivity and photo allergies. Sun can also cause the skin to lose its elasticity and form wrinkles, leading to premature ageing. Dermatosis may also be caused due to over-exposure to solar rays. In extreme cases, some people can develop skin cancer.
Outdoor activities including typical field-related jobs and sporting activities expose the skin to sun. It has been estimated that nearly 75 percent of the sun-inflicted skin damage on the average person's skin over a lifetime is the result of being just outdoors. Hence we require a protection so that we can expose ourselves to the sunlight without getting harmed. These concerns have been heightened by evidence that the earth's ozone layer has suffered severe depletion in recent years. Ozone is recognized as the stratospheric component shielding against the harmful forms of ultraviolet radiation. But still 5% of the sunrays coming to the earth are composed of the ultraviolet rays. These ultraviolet rays are composed of the shorter-wavelength (290-320 nm) UVB rays that cause indirect sun tanning and the longer-wavelength (320-400 nm) UVA rays that are responsible for direct sun tanning. Sunscreen compositions offer a scientific solution to the above-identified harmful effects of over-exposure to the ultraviolet rays.
Topical application sunscreen formulations are known. Sunscreen active are generally classified as organic sun screeners or inorganic sun screeners. Organic sun screeners absorb strongly at specific wavelengths and are transparent to visible light. However, some organic sun screeners such as Oxybenzone are known to cause photo allergic reactions. Inorganic sun screeners such as Titanium dioxide at higher levels leave visible residue referred as whitening of the skin.
To overcome these allergic side effects of organic sun screeners and non-aesthetics of inorganic sun screeners, there exist the need for devising newer formulations, that can protect the skin from the harmful effects of the ultraviolet radiations of sun without any undesirable side effects. It is against this background the present invention has been brought out.
U.S. Pat. No. 6,500,869 to Driller et al. discloses a sun protection formulation in solid or liquid form containing organic or inorganic sunscreen filters for a prophylactic action. Disclosed in this patent are substances of cinnamic acid derivatives, in particular octyl p-methoxycinnamate that function not only as light protection filters, but also as solvents for other UV filters and are therefore often used in combination with various filters.
U.S. Pat. No. 6,537,529 to Bonda et al. discloses a method of preparing a sunscreen including a solvent system and a filter system, as well as sunscreen compositions and compounds for producing sunscreen compositions.
U.S. Pat. No. 5,773,014 to Perrier et al. discloses a composition to inhibit the formation of unwanted skin pigmentation. The active components of the composition include extracts of selected plants, namely, mulberry, saxifrage, grape and scutellaria root; and, preferably, ethylene diamine tetra acetic acid (EDTA).
U.S. Pat. No. 6,440,402 to Gonzalez et al. discloses the synergistic action of Kaempferia galanga root extract in sunscreen formulation. The invention also discloses a method comprising introducing into the composition an amount of extract of Kaempferia galanga plant sufficient to enhance the photostability of the sunscreen active.
U.S. Pat. No. 5,756,099 to Simpson et al. discloses a process of preparing natural, organic, topical tanning sunscreen compositions comprising extracting the embryonic, spongy mass of tissue of the coconut from the drupe and adding it to the flesh of papaya in a proportional ratio of 1:3.
Sunscreen compositions comprising herbal extracts that can act as antioxidants are known in prior art. Sunscreen compositions containing herbal extracts such as green tea, aloe vera, calendula, chamomile rosemary are also known in the art. Further, it is known in the art to devise sunscreen compositions having cinnamic acid esters, wherein the cinnamic acid esters act as sunscreen actives. The present invention is distinct from the above prior art compositions as described hereunder.